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WIND FARMS Wind energy, while it seems intuitively to be a sustainable and eco-friendly source of renewable energy, has proven to be inefficient, extremely costly, and environmentally damaging.
The cost of wind energy is very high. Eskom can charge 55c a kilowatt-hour but the tariff ceiling for wind energy has been set at R1.15. Bids are not expected to be significantly below that ceiling. The environment pays a high price too. The visual impact is massive: wind turbines are huge structures, standing 150m from ground to blade tip. Add maintenance roads and power lines, and the environmental footprint is substantial. The foundation of each turbine is 100 cubic metres of reinforced concrete, sunk into the earth with obvious effects on wetlands and ground water. The effect on birds and bats is serious: bats approaching turbines get the bends – a lethal syndrome known as baro-trauma, and certain birds – including our own Denham's Bustards and Blue Cranes – are particularly vulnerable to collision with turbines and power lines because of blind spots in their visual fields. Carbon emissions are not even reduced by wind energy. The back-up power stations emit almost as much carbon (94%) as the wind facility supposedly saves. And on top of that, wind turbines actually need to draw electricity from the grid to operate. Turbines use electricity to prevent yaw, for blade-pitch control, for lights, controllers, communication, sensors, metering, hydraulic locks for very high wind conditions, pump, cooler and filtering system in the gearbox, and so on, and the emissions from that power use effectively wipe out the few remaining percentage points. KOUGA WIND FARMS The Kouga area has been targeted by prospective wind farm developers, because of its favourable wind profile. No fewer than ten wind farms are proposed, with a total of over 500 turbines. The consequences, if all ten are approved, are serious: a major change in the rural landscape, widespread interference with wetlands, important impacts on bird habitats and inescapable threats to the bat population, to name only some.
Three local wind farms were selected in the first round of bidding and can apply for licences to produce power. They are Mainstream’s Jeffreys Bay Wind Project, Red Cap’s Kouga Wind Farm and the van Staden’s Wind Farm at Blue Horizon Bay. The 9 turbine van Staden’s project is in the Nelson Mandela Bay Municipality and beyond the area served by the St Francis Kromme Trust. The closest to St Francis is the Red Cap Kouga Wind Farm, with construction due to start in July 2012, for electricity production from the second quarter of 2014. This 32 turbine plant will have a 13km power line to connect it to the St Francis Bay substation, and both the turbines and the power line are of deep concern to the St Francis Kromme Trust. This particular site is the heartland of the Denham’s Bustard, a large and handsome terrestrial bird found in unusually large numbers here. This species is listed as vulnerable by the Red Data Book, and research shows that large numbers of both bustards and cranes are being killed by power lines in South Africa. Red Cap has a second proposed site, the so-called Western Cluster, a few kilometres to the west of the approved site described above. Mainstream’s Jeffreys Bay Wind Farm, a 60 turbine development on the north side of the N2, lies between Humansdorp and Jeffreys Bay. Construction is scheduled for the last quarter of 2012, with operations to begin in December 2013. The St Francis Kromme Trust sees the Jeffreys Bay Wind Farm as a test case for wind power: experience in Europe is that wind is a poor power source, that wind farms use almost as much power as they produce, and that wind turbines only operate about 30% of the time. But we can only know for certain what will happen in South Africa when we have a working wind farm to judge by. Since the Jeffreys Bay project will be relatively unobtrusive visually, there are relatively few endangered species on the site, and it is located right next to the Melkhoutsbosch substation so power line requirements are minimal, this wind farm poses few obvious problems and the Trust does not oppose it. Other proposals in the pipeline: RES Oyster Bay Wind Energy Facility: view the Final Environmental Impact Report at www.savannahsa.com/projects Tsitsikamma Community Wind Energy Facility: view the Final Environmental Report at www.savannahsa.com/projects Deep River Wind Energy Facility: view the Final Environmental Impact Assessment at www.savannahsa.com/projects Happy Valley Wind Energy Facility: view the Final Environmental Report at www.savannahsa.com/projects Ubuntu Wind Energy Project: view the Final Environmental Report at www.publicprocess.co.za Banna ba Pifhu Wind Energy Project: view the Draft Scoping Report at www.publicprocess.co.za Broadlands Photovoltaic Power Project: view the Draft Basic Assessment Report at www.publicprocess.co.za
For further information, contact Maggie Langlands on 042-294-1075 or 082-458-8063 |
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The efficiency of wind is limited by its intermittent nature. An Eskom spokesperson estimates that a wind farm is doing well if its putting power into the grid 27% of the time . The actual amount of power produced is minimal, about a quarter of the installed capacity . And because the grid can't depend on a steady flow of power from a wind farm it's necessary to have power station back-up to come in when the wind drops – or blows so hard that the turbines shut down. The back-up power stations have to be kept constantly running, at least in low-cycling mode, even while the wind farm is generating power, to keep the furnaces warm so that instant base load power can be produced when it's needed.
